This section is intended to provide background information to facilitate a better understanding of various technologies described herein. As the section's title implies, this is a discussion of related art. That such art is related in no way implies that it is prior art. The related art may or may not be prior art. It should therefore be understood that the statements in this section are to be read in this light, and applicant neither concedes nor acquiesces to the position that any given reference is prior art or analogous prior art.
Seismic exploration may utilize a seismic energy source to generate acoustic signals that propagate into the earth and partially reflect off subsurface seismic reflectors (e.g., interfaces between subsurface layers). The reflected signals are recorded by sensors (e.g., receivers or geophones located in seismic units) laid out in a seismic spread covering a region of the earth's surface. The recorded signals may then be processed to yield a seismic survey.
In a spread for a seismic survey, a plurality of sources and receivers may be arranged in a grid, such that the recorded data from the wavefields may substantially cover the entire area of exploration and with sufficient resolution to detect the variation of the sub-surface structure over small spatial distances. The wavefields recorded by the receivers may be a result of the superposition of many waves having different paths through the earth's sub-surface before finally reaching the receivers. This may make the reconstruction of the earth sub-surface difficult. One objective of seismic data processing is to separate the wavefields into coherent waves in connection with creating an accurate image of the earth's sub-surface layers. Because seismic data acquisition is quite expensive, it is desirable to increase the distance between the grid points and still provide sufficient resolution or use the same or tighter grid and achieve finer resolution.